The invention relates to a cargo gate for holding at least one cargo item at a predetermined position within a cargo hold of an aircraft, a cargo deck with a corresponding cargo gate and a method for converting or fitting out a cargo deck for the purpose of airdropping cargo items during a flight.
For transporting air cargo, the cargo items to be transported, in particular containers or pallets, which are preferably fabricated in accordance with specific standards, are fastened inside the cargo hold by means of locking elements on the cargo hold floor.
In the military cargos sector, there is a special standard in accordance with which the containers or pallets have edge-side notches at regular intervals, in which locking lugs of locking devices engage for holding the containers in the X-direction, that is to say in the longitudinal direction of the aircraft. These locking lugs are usually configured pivotably in the plane of the cargo hold, that is the X-Y plane. However, there are also configurations in which the locking bars can be pivoted up or down. The process is particularly critical when cargo items are unloaded via parachutes during a flight. In this case, when the rear cargo hatch is opened and the cargo is supposed to be dragged out of the cargo hold by previously ejected parachutes, the locking elements must then be reliably opened as otherwise there is a risk of crashing particularly when flying low. Corresponding locking devices are disclosed in EP 0 771 726 A2 and in U.S. Pat. No. 4,372,715.
Among other things, however, cargo items which do not have appropriate notches or do not have notches of adequate shape for engagement of the locking lugs also have to be dropped.
Moreover, there are cargo items which do not conform to the specified standard or which have a standard that is designed for a different cargo loading system. One example of such cargo items are airdrop containers A-21 and A-22 whose base plates generally consist of 12 to 20 mm thick plywood. During the flight, such cargo items are fastened towards the front by means of a buffer stop. Further fixing is effected, for example, by means of loops, such as are illustrated in U.S. Pat. No. 4,426,051. Alternatively, cargo gates can be provided which are mounted between the individual cargo items in the longitudinal direction. Such cargo gates (e.g. CDS gates) have a flat retaining element which essentially extends in the Y-Z plane in order to hold the cargo items in the cargo hold. The cargo gates particularly absorb forces which act in the longitudinal direction (that is in the X-direction) of the aircraft. It is known to lower such cargo gates electrically or pneumatically during the flight for airdropping of the cargo items. The known cargo gates are normally independent systems which have a very complex construction and are folded down or actuated by means of independent servo-motors or tripping mechanisms. Therefore a great deal of time is required for the conversion of a cargo hold corresponding to a specific loading requirement. Moreover, connection of the systems is time-consuming and prone to error. Added to this, is that the known cargo gates are very heavy with the result that they contribute significantly to the overall weight of the aircraft.
Based upon this prior art, it is an object of the present invention to provide an improved cargo gate. In particular, the cargo gate according to the invention should make it easier to reconfigure and individualise a cargo deck.
In particular, the object is achieved by a cargo gate for holding at least one cargo item at a predetermined position within a cargo hold of an aircraft which comprises:
at least one retaining element;
at least one fastening device having at least one articulation for articulatedly fastening the retaining element to a cargo hold floor such that the retaining element can be pivoted from an operative position for holding the at least one cargo item into an inoperative position, wherein the retaining element can be traversed by the at least one cargo item in the inoperative position and the retaining element is provided with a stop which can be operatively connected to a pivotable locking lug of a locking device such that the locking lug holds the retaining element in the operative position thereof.
A central idea of the present invention is therefore to provide a very easily constructed, preferably purely mechanical cargo gate, which by means of existing locking devices can be held in an operative position and released. An appropriate cargo gate can be constructed very easily and robustly. Since this possibly does not include any electrical or pneumatic elements, it is unlikely that such a cargo gate will fail. Moreover, cargo decks which are fitted out for standardised cargo items can be converted without major effort such that non-standardised or differently standardised cargo items can be also be airdropped. An essential point of the present invention is that the retaining element is provided with the stop which is configured in such a way that it can be operatively connected to a locking device, in particular to a locking lug of a locking device. The locking lug of the locking device thus functions as a release mechanism while the cargo gate is a passive element.
The stop may be pivotable by means of a stop articulation from a stop position into a lowering position. The locking devices for military use already described in the introduction are frequently installed with side guides which partially encompass the cargo items such that they are secured in the Z-direction of the aircraft—that is to say upwards. The stop is preferably configured in such a way that it can engage in a guiding region formed by the side guide which also contains the locking lug. The stop is articulatedly supported to prevent it from jamming on folding down into the inoperative position. In this respect, it can be pivoted in an appropriate manner on folding down.
The stop is preferably pivoted about a stop rotational axis from its stop position into the lowering position. This stop rotational axis may run perpendicular to the rotational axis of the retaining element (pivoting of the retaining element between the operative and inoperative position thereof).
The cargo gate may comprise at least one spring assembly which loads the stop into the lowering position—that is to say the position which does not hinder folding down of the cargo gate. For secure folding down of the retaining element from the operative position thereof into the inoperative position, it is helpful if the stop is pivoted into the lowering position as soon as no force or only a slight force acts on it. An appropriate spring assembly which loads the stop into this position can be provided for this purpose.
The articulation for pivoting the retaining element from the operative position thereof into the inoperative position may comprise a pivot articulation which defines a rotational axis. For the articulated support of the retaining element, a pivot articulation is to be preferred as it enables the retaining element to be folded away in the direction of airdropping such that movable elements cannot become wedged.
The stop may protrude beyond the retaining element in the inoperative position in a direction parallel to the rotational axis. This is preferably the Y-direction of the aircraft.
The fastening device may comprise a holding device, in particular a quick-closing element, e.g. a holding slide, for fastening in a perforated rail and/or a seat rail of the cargo hold.
The fastening device is preferably reversibly mountable on the cargo deck such that it is easy to alter the position of the cargo gate. All the known mechanisms in this field may be used for fastening the cargo gate on the cargo deck. The fastening device is preferably anchored in perforated rails and/or seat rails which are provided on the cargo hold floor. According to the invention, appropriate adapters can also be provided in order to anchor the fastening device at any point within the cargo hold. The holding devices make it possible to reconfigure the cargo deck quickly. Thus the cargo deck can be individually adapted to different cargo items, with varying lengths for example. By means of the positioning within the perforated rails and/or seat rails, it is possible in each case to find a position for the cargo deck in which a corresponding locking element or corresponding locking device is available.
The retaining element may be a flat and/or grid-shaped element which extends along a retaining element plane. The cargo gate, in particular the fastening device, may be configured in such a way on a cargo deck for fastening of the retaining element that the retaining element plane extends in the operative position thereof essentially perpendicular to the X-direction of the cargo deck, in particular of the aircraft.
The cargo gate may be configured in such a way that, when it is in the mounted state on the cargo deck, it spans at least one third, in particular at least half, in particular at least two thirds, of a cargo loading path of the cargo deck.
The retaining element may have a width of at least 60 cm or at least 70 cm or at least 80 cm or at least 90 cm or 100 cm. The width of the retaining element may be defined such that it describes the extension of said retaining element along the rotational axis.
The retaining element may have a height of at least 5 cm or at least 7 cm or at least 10 cm or at least 12 cm or at least 15 cm. The height of the retaining element may be defined such that, in the operative position of the retaining element, it describes the shortest distance between the rotational axis and the highest point of the retaining element.
The object referred to above is furthermore achieved by means of a cargo deck of an aircraft which extends along an X-direction (longitudinal direction of the aircraft) and a Y-direction (transverse direction of the aircraft), wherein the cargo deck comprises:
at least one cargo gate as already described previously;
at least one locking device having a locking lug which is pivotable from an operative position of the locking lug into a loading position, wherein the cargo gate is arranged in such a way that the locking lug is operatively connected to the stop in the operative position of said locking lug in order to hold the retaining element in the operative position thereof.
Thus, in the operative position of the retaining element, the locking lug absorbs at least some of the forces acting on the cargo gate. These forces preferably act in the X-direction on the cargo gate, in particular its retaining element, and are transferred into the cargo deck via the locking lug. Similar advantages emerge, such as have already been described in connection with the cargo gate alone.
The cargo deck may comprise at least one side guide running along the X-direction for holding and guiding the cargo items, wherein the at least one locking device is arranged in such a way that its locking lug protrudes into a guiding region of the side guide. A side guide extending in the X-direction is preferably located on each side of the cargo deck. Similar side guides with or without locking device may be provided centrally, for example, in the aircraft such that two loading paths are created on the cargo deck. The articulatedly supported stop already described may protrude on one side or on both sides into the guiding region defined by the side guides and may contact the locking lugs therein. After lowering the locking lugs, the retaining element is automatically pivoted into the inoperative position due to the forces acting on it.
The cargo deck may comprise a plurality of identical or similarly configured locking devices which protrude into the guiding region of the side guides to hold cargo items, in particular to absorb forces acting in the X-direction, wherein fixing points, in particular seat rails or perforated rails are provided on the cargo deck in order to fix the at least one cargo gate at positions in which in each case at least one locking lug of the plurality of locking devices can be operatively connected to the stop of the at least one cargo gate. For example, the locking devices may be arranged at predefined, in particular regular, intervals. The fixing points make it possible to fix at least one cargo gate at various positions such that its stop can be operatively connected to a locking lug of a locking device.
The locking device may comprise an adjusting mechanism for remotely controlled, in particular electrical and/or pneumatic actuation. The functional elements (e.g. locking devices, power drive units with rollers, etc.) can preferably be remotely controlled such that it is possible to comply with a specified time schedule. A computer, preferably a Mission Control Computer, preferably takes over appropriate remote control.
The adjusting mechanism may be configured in such a way that the locking device can be brought into at least three states, namely:
a loading state, in which the locking lug is in the loading position;
a holding state, in which the locking lug is in the operative position and is fixed; and
a release state, in which the locking lug is in the operative position thereof but can then be pivoted out of the operative position into the loading position if a force acting on the locking lug, which in particular is exerted by the cargo gate in the X-direction, exceeds a predetermined amount.
In this respect, it is possible to provide a cargo gate which does not, like conventional cargo gates, lower on a specific electrical signal but which, until airdropping takes place, provides a certain holding force that can only be overcome by the application of additional forces.
Such a cargo gate prevents cargo items from being airdropped too early or unintentionally.
The adjusting mechanism may comprise a spring assembly which defines the predetermined amount of the force acting in the X-direction.
The spring assembly may comprise a tensioning device which, in particular, is electromotively adjustable, for adjusting a preload of a retention clip. This preload can define the release point in the holding state of the locking device. The holding spring thus specifies the force which must be applied in order to release the cargo gate.
The adjusting mechanism is preferably configured in such a way that in addition to the loading state, the holding state and the release state, it can capture the locking device in at least a fourth state, namely an airdropping state in which the locking lug is in the loading position. In this respect, this state is essentially identical to the loading state. The retaining element preferably pivots into the inoperative position on assuming this state. The adjusting mechanism is configured in such a way that this state can preferably be initiated by means of an input device, e.g. at the touch of a button, or via control by the computer. In this respect, the cargo gate according to the invention offers all the functionalities that have also been offered by the customary, significantly heavier cargo gates.
The retaining element may comprise at least one recess to accommodate functional elements attached on the cargo deck in the inoperative position. Since, in its inoperative position, the flat retaining element covers a significant section of the cargo deck, it may be advantageous if recesses are provided which accommodate corresponding functional elements and do not prevent the use thereof. For example, a drive roller may protrude in the inoperative position through the recess into the cargo hold such that the cargo items can be transported on the cargo deck with low friction.
The object referred to at the outset is moreover achieved by means of a method for converting or fitting out a cargo deck for the purpose of airdropping cargo items during a flight, wherein the cargo deck comprises a plurality of locking devices, arranged in particular on the edge region of the cargo deck along an X-direction, for holding cargo items, wherein the method additionally comprises, in the step of fastening, a plurality of cargo gates, each of which comprises an articulation for pivoting a retaining element from an operative position thereof into an inoperative position, in such a manner on the cargo deck that one stop of each cargo gate respectively can be operatively connected to one pivotable locking lug of each locking device respectively in order to hold the relevant retaining element in the operative position thereof.
Further advantageous embodiments emerge from the claims. An embodiment of the invention will be explained subsequently in greater detail on the basis of drawings.